Method handle

mcp/logging.go:158–201

(ctx context.Context, r slog.Record)

}

func (h *LoggingHandler) handle(ctx context.Context, r slog.Record) error {
	// Observe the rate limit.
	// TODO(jba): use golang.org/x/time/rate.
	h.mu.Lock()
	skip := time.Since(h.lastMessageSent) < h.opts.MinInterval
	h.mu.Unlock()
	if skip {
		return nil
	}

	var err error
	var data json.RawMessage
	// Make the buffer reset atomic with the record write.
	// We are careful here in the unlikely event that the handler panics.
	// We don't want to hold the lock for the entire function, because Notify is
	// an I/O operation.
	// This can result in out-of-order delivery.
	func() {
		h.mu.Lock()
		defer h.mu.Unlock()
		h.buf.Reset()
		err = h.handler.Handle(ctx, r)
		// Clone the buffer as Bytes() references the internal buffer.
		data = json.RawMessage(slices.Clone(h.buf.Bytes()))
	}()
	if err != nil {
		return err
	}

	h.mu.Lock()
	h.lastMessageSent = time.Now()
	h.mu.Unlock()

	params := &LoggingMessageParams{
		Logger: h.opts.LoggerName,
		Level:  slogLevelToMCP(r.Level),
		Data:   data,
	}
	// We pass the argument context to Notify, even though slog.Handler.Handle's
	// documentation says not to.
	// In this case logging is a service to clients, not a means for debugging the
	// server, so we want to cancel the log message.
	return h.ss.Log(ctx, params)
}